There were some videos of an early map-making SDK released
4 years ago, but little information since apart from the snippets below.
Quote from Luthier's 30 Aug 2011 update
<snip>
"Following that, we have other things in the works. We are finally ready to start knocking out SDKs, with the map making SDK being the first one you’ll see – quite soon, too! We’ll release more details on that, and on the plane-making SDK, after the upcoming beta patch is fully tested and goes live." <snip> See
http://forum.1cpublishing.eu/showthread.php?t=25747
Quote from Luthier's 18 Oct 2011 update
v1.05.15950 is now live! What to expect next.
<snip>5. SDK. As promised earlier, still planning to release a map-making SDK in the near future. More details will be released when we are ready for them.<snip> See
http://forum.1cpublishing.eu/showthread.php?t=27146